To uncase is to remove something from its case or covering—to draw a sword from its scabbard, unwrap a flag for display, or extract an instrument from its protective container.
The word is uncommon in everyday speech, appearing mainly in military or ceremonial contexts: The honor guard uncased the colors.
1. unpack — remove, Take something away; unbox (Remove from packaging); unload (Remove contents from); unwrap (Remove outer covering); extract · take out · empty · unpackage · decant · retrieve
2. reveal — uncover, Reveal what's hidden; expose (Make known publicly); unveil (Reveal something hidden); disclose (Reveal hidden information); divulge · open · unseal · unsheathe · unwrap · extract · display · exhibit · bring forth · lay bare